Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease

Background. Cardiovascular diseases (CVDs) are defined as conditions involving decreased blood flow to the heart that can lead to heart attacks, stroke or other disorders. CVDs are a common cause of death in low- and middle-income countries. In South Africa (SA) in particular, CVD is the leading cause of death after HIV/AIDS, responsible for 1 in 6 deaths. CVD risk factors include unhealthy diets, hypertension, obesity, high cholesterol levels and diabetes. Omega-3 fatty acids may have a protective role in the risk of developing heart disease.Objectives. To evaluate the consequences of an increased intake of fish and plant-based omega-3 fatty acids on the risk of CVD mortality and events.Methods. The inclusion criteria for this review were randomised controlled trials (RCTs) lasting at least 12 months, which investigated men and women aged ≥18 years. These participants had to be at any risk of CVD while receiving dietary supplements and an advised diet to promote the intake of omega-3. This diet included oily fish, fish oils and seeds rich in omega-3. Comparisons with the interventions included the participants’ usual diet, no advice, no supplements, placebo or lower-dose omega-3. The review evaluated the effectiveness of these interventions on primary (e.g. CVD deaths and events), secondary (e.g. major adverse cerebrovascular or CVD events, body weight and other adiposity measures, and lipids) and tertiary (e.g. blood pressure and side-effects) outcomes.Results. Evidence from this review indicates that increasing the intake of long-chain omega-3 fatty acids (LCn3) or alpha-linolenic acid (ALA) probably has little or no effect on all-cause CVD or coronary heart disease mortality. Evidence was of moderate certainty, except for all-cause mortality, where there was a high certainty.Conclusions. According to moderate- to high-certainty evidence, short-chain fatty acids and LCn3 have little or no effect on mortality or cardiovascular health. However, omega-3 ALA slightly reduces the risk of CVD events and arrhythmias

Reduced stiffness buckling analysis of aboveground storage tanks with thickness changes

The Reduced Stiffness Analysis (RSA) to compute lower bounds to buckling loads of shells has been employed by a number of researchers as a simple way to evaluate the buckling capacity of shells that display unstable behavior and imperfection-sensitivity. It allows the use of simple eigenvalue analysis, without having to perform incremental nonlinear analysis, and is based on the physical behavior of the shell which recognizes that a significant contribution to the stability of a shell under lateral pressure is provided by its membrane stiffness. Unstable post-critical behavior is associated with the loss of this stabilizing membrane contribution. Past use of the approach has been mainly restricted to cases of uniform shell thickness and uniform pressures in the circumferential direction, in which case analytical solutions are possible. Recent applications by the authors and other researchers have shown ways to compute the lower bounds using finite element analysis, for which a modified eigenvalue analysis is constructed by neglecting the membrane contributions to the matrix containing the initial stresses. This paper illustrates the application of the methodology to cases of pressure loaded shells with thickness changes in the meridional direction. A semi-analytical finite element code has been employed for the buckling analysis when uniform pressures act on aboveground steel tanks. The tanks are representative of those constructed for the oil industry, with diameter to thickness ratios of the order of 3000, and height to diameter ratios lower than one.Fil: Jaca, Rossana Claudia. Universidad Nacional del Comahue; ArgentinaFil: Godoy, Luis Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Estudios Avanzados en Ingeniería y Tecnología. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Estudios Avanzados en Ingeniería y Tecnología; ArgentinaFil: Croll, James G. A.. University College London; Reino Unid

A penalty approach to obtain lower bound buckling loads of imperfection-sensitive shells

Fil: Godoy, Luis A. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Godoy, Luis A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Estructuras; Argentina.Fil: Jaca, Rossana C. Universidad Nacional del Comahue. Facultad de Ingeniería. Departamento de Ingeniería Civil; Argentina.Fil: Sosa, Eduardo M. West Virginia University. Civil and Environmental Engineering Department; Estados Unidos.Fil: Flores, Fernando G. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Flores, Fernando G. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Estructuras; Argentina.The strategy of Reduced Stiffness (or Reduced Energy) Analysis, in which selected energy components are eliminated to account for mode interaction and imperfection-sensitivity in a simplified way, was developed by Croll and co-workers since the early 1980s. This physical interpretation allows the formulation as an eigenvalue problem, in which the eigenvalue (critical load) is a lower bound to experiments and to nonlinear incremental analysis. This paper considers the computational implementation of both reduced stiffness and reduced energy approaches to the buckling of shell structures by means of perturbation techniques and penalty parameter methods. The structural configurations of interest in this work are cylindrical shells with or without a roof. The reduced stiffness approach has been implemented in a special purpose finite element code for shells of revolution, whereas the reduced energy methodology was implemented in a general purpose finite element code. The present results are compared with geometrically nonlinear analysis including geometric imperfections. Achievements and difficulties in extending the methodologies to complex problems in engineering practice are highlighted.http://congress.cimne.com/PANACM2015/frontal/doc/EbookPANACM2015.pdfFil: Godoy, Luis A. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Godoy, Luis A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Estructuras; Argentina.Fil: Jaca, Rossana C. Universidad Nacional del Comahue. Facultad de Ingeniería. Departamento de Ingeniería Civil; Argentina.Fil: Sosa, Eduardo M. West Virginia University. Civil and Environmental Engineering Department; Estados Unidos.Fil: Flores, Fernando G. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Flores, Fernando G. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Estructuras; Argentina.Ingeniería Estructura

Challenges for ecolabeling growth: lessons from the EU Ecolabel in Spain

Purpose The European Ecolabel (EU Flower) has the mission to encourage cleaner production and influence consumers to promote Europe's transition to a circular economy. Nonetheless, little is known about EU Ecolabel evolution; it is not clear what the drivers that encourage its implementation are. Thus, this study aims to assess the growing acceptance of the EU Ecolabel in the European Union, and Spain more specifically, by examining product and service categories and geographical regions. Methods The methodological approach taken in this study is a mixed methodology based on the triangulation method by consulting the EU Ecolabel scheme database, EU Ecolabel delegates from some autonomous regions, and the academic literature. Also, a geographic analysis was run in the ArcGIS Software with data about the accumulation of licenses assigned in 2016. Results and discussion The analysis shows that most products in Spain that have been awarded the EU Ecolabel belong to the following categories: Do-It-Yourself Products (paint and varnish), Paper Products, Cleaning Up Products, and Electronic Equipment. At the same time, the study showed that this ecolabel faces significant obstacles in its diffusion, such as the competition with environmental labels launched previously in Europe and other regional labels. Conclusions The results of this study indicate the existence of five drivers that may encourage the implementation of EU Flower in a region: (1) public management, (2) communication strategy, (3) sustainable public procurement criteria, (4) local income per capita, and (5) international trade incentives. Finally, this study provides essential recommendations for policymakers to trigger ecolabeling practices such as the need to improve the understanding of the EU ecolabel impact in different levels of activity, which means countries, regions, industrial clusters, firms, and consumers. Also, this investigation identifies areas for further research, and it expresses the need to develop business case studies about ecolabeling with the objective to visualize this phenomenon as an eco-innovation process

Comportamiento poscrítico de tanques de almacenamiento de combustible sometidos a la acción de viento y fuego

Un escenario de incendio en una batería de tanques de almacenamiento de combustible presenta muchas variables involucradas que interaccionan entre sí y modifican la distribución de temperaturas que actúan sobre un tanque en particular. Los tanques adyacentes a otro en situación de incendio son susceptibles de daño estructural que puede contribuir al desarrollo de un efecto dominó involucrando a otros tanques en el incendio. En trabajos anteriores se analizó la existencia de viento actuando simultáneamente con fuego en un tanque, esta acción produce una inclinación de la llama y una modificación de la distribución de temperaturas sobre el tanque en estudio. Este trabajo plantea un análisis estructural de un tanque metálico considerando simultáneamente la acción del viento sobre la estructura y la distribución de temperaturas obtenida por transferencia de calor desde la llama inclinada por el viento. El tanque en estudio se modela por elementos finitos mediante un código de propósitos generales (ABAQUS) y se realiza un análisis no lineal geométrico con imperfecciones geométricas para evaluar el comportamiento poscrítico. El viento actuando sobre el tanque genera una deformada que actúa como una imperfección geométrica sobre la estructura perfecta que afecta el comportamiento poscrítico. Se consideran como imperfecciones geométricas las formas de modo asociadas a la carga térmica y viento, y además la deformada por acción del viento. En el análisis se incluye la variación de las propiedades mecánicas del acero con la temperatura. Para esta simulación de fuego estudiada, el comportamiento inestable se produce a temperaturas del orden de la mitad de las correspondientes al estado estacionario.Publicado en: Mecánica Computacional vol. XXXV no.38Facultad de Ingenierí

Increasing Engineering Students’ Involvement in Circular Economy Practices.

The circular economyhas become a topic of intense interest for policymakers, scholars and business managers because it has proven to bea new paradigm to achieve the sustainability of our society. However, the main efforts made in thecircular economy cannot be limited tothe actions ofprofessional or experts. We believe that if we intend to meet current needs without compromising the ability of future generations to meet their own needs, we mustteach present generations the principles for achievingeconomic, social and environmentalsustainability in the short, mediumand long-term. This paper highlights the use of participatory guided activitiesinstead of traditional coursesto teach and engage engineering students with circular economy practices

The use of anticoagulants in patients hospitalised with COVID-19

In this Cochrane Corner, we highlight the main findings of a Cochrane Review by Flumignan et al. entitled ‘Anticoagulants for people hospitalised with COVID‐19’ and discuss the implications of these findings for research and practice in South Africa. In particular, we underscore the need for additional, high‐quality, randomised controlled trials comparing different intensities of anticoagulation in patients with COVID‐19 illness. Individuals in the intensive care unit and those hospitalised with another illness who are incidentally found to be infected with SARS‐CoV‐2 should still only be treated with prophylactic‐dose low‐molecular‐weight heparin

Diseño de una batería de tanques de almacenamiento de combustible : Análisis térmico

El diseño de una batería de tanques de almacenamiento de combustible contempla diferentes aspectos que hacen a la eficiencia de la planta, tales como minimizar costos y facilitar su operación, y otros aspectos asociados a la seguridad de la misma que intentan minimizar riesgos potenciales. Esto es, si accidentalmente se iniciara un incendio en uno de los tanques, las distancias mínimas reglamentarias entre tanques pretenden minimizar la posibilidad de eventos en cadena que pudieran afectar a toda la planta. En este trabajo se computan niveles de radiación incidente y distribución de temperatura en tanques adyacentes al tanque bajo fuego considerando distintos diámetros y diferentes distancias entre ellos. Esta distribución es utilizada posteriormente para determinar la deformación estructural ocasionada en cada caso, a efectos de evaluar la posibilidad de un efecto dominó por colapso de tanques vecinos a la llama. Las temperaturas máximas alcanzadas y las deformaciones provocadas en el material son estimadas por elementos finitos utilizando un análisis secuencial implementado en un código de propósitos generales. Los resultados indican que en una planta diseñada con separacionesde un diámetro entre tanques de gasolina, el incendio de uno de los tanques conduce a temperaturas máximas del orden de 400°C en los tanques vecinos. Sin embargo, las temperaturas pueden ser hasta 200°C superiores si las distancias se reducen a las mínimas reglamentarias, ocasionando deformaciones que comprometen aún más su integridad estructural y aumentan el riesgo potencial de extensión del incendio a toda la planta.Publicado en: Mecánica Computacional vol. XXXV no.37Facultad de Ingenierí

Modelado de la estabilidad de naves industriales con asentamiento local de apoyos

El descenso diferencial de apoyos genera desplazamientos fuera del plano en los cerramientos laterales de naves industriales metálicas, pudiendo comprometer las condiciones de servicio. En este trabajo se estudia la respuesta estructural de cerramientos laterales flexibles de galpones metálicos con diferentes geometrías debido a asentamientos diferenciales, proponiendo configuraciones de rigidizadores a fin de reducir dichos desplazamientos. La modelación numérica se realiza por elementos finitos mediante el código de propósitos generales ABAQUS usando elementos de cáscara tanto para el cerramiento como para las correas y considerando no linealidad geométrica. Los resultados numéricos de una de las geometrías estudiadas se validan con los provenientes de un modelo físico a escala reducida. Para diferentes relaciones entre la altura del cerramiento y separación entre pórticos se plantean configuraciones alternativas de sección de correas y separación entre ellas, comparando con los desplazamientos admisibles para condiciones de servicio. En todos los modelos estudiados, correspondientes a diferentes relaciones geométricas de la placa de cerramiento, se observa un cambio en el patrón de deformaciones por la presencia de los elementos de rigidización lateral y una reducción de los desplazamientos al aumentar la inercia de las correas y disminuir su separación. En algunas de las geometrías estudiadas los desplazamientos fuera del plano permanecen mayores a los admisibles.Publicado en: Mecánica Computacional vol. XXXV, no. 39Facultad de Ingenierí

Meeting high precision requirements of additively manufactured components through hybrid manufacturing

A hybrid approach combining the laser powder bed fusion (LPBF) process and post-processing operations through 5-axis milling was employed to manufacture a Ti6Al4V aerospace component. From the design step, the requirements and needs in all the stages of the Hybrid Additive Manufacturing process were taken into account. A numerical simulation of distortions promoted by residual stresses during the additive process was employed to consider material allowance. The status of the as-built and post-processed component was analysed through scanning and CMM inspection and roughness measurements. The 3D scanned model of the as-built LPBF-ed component was used to understand the distortion behaviour of the component and compared to the numerical simulation. Finally, 5-axis milling operations were conducted in some critical surfaces in order to improve surface quality and dimensional accuracy of the as-built com- ponent. The inspection of the as-built and post-processed component showed the improvement achieved through the proposed hybrid approach. The work aims to provide the baselines needed to enable the metal Hybrid Additive Manufacturing of components with complex geometries where mandatory precision is required by integrating high accuracy machining operations as post-processing technique